Piston packing



Patented dan. ll, 1924.

uNHTeo sTaTes .A tiene raTENT carros.

CHARLES n. sHoR'r, or DETROIT, MICHIGAN, Assrenor. rro GENERAL morons coa PO l" TION, 0F DETROIT, MICHIGAN, A CORPORATION 0E DELAWARE.

I PISTGN PACKING.

Application led ecember 1, 1919. Serial No. $41,746.

To all whom t may concern.'

Be it known thatll. CHARLES R. SHORT, a lsubject of the King of Great Britain, and a resident of Detroit, county of W'ayne, and State of Michigan, have invented certain new and useful Improvements in Piston Paekings, of which the following is a tull, clear, concise, and exactdescription, `such as will enable others skilled in the art to which the invention relates to make and use the same, reference being made therein to the accompanying drawings, which form a part of this specification.

The invention relates to piston packing of the type comprising a plurality of rings insertedin a groove in the piston, and is es vpecially designed `for use in connection with the pistons of internal combustion engines.

lln piston packing of the kind generally employed in, such engines, one-piece rings are made of approximately the same width as the groove in the piston, and 4are held outwardly against the cylinder wall by their own resilience. Rings of this type however, although they may fit closely to the wall of the cylinder, have no provisionfor maintaining a tight fit with the Walls of the groove itself. iLeakage and pumping of oil therefore take place around the rlng within the groove. lt has been proposed to remedy this defect by the use of divided rings or a plurality of rings in the same groove so arranged that a tight fit is produced both with4 the cylinder wall and with at least one wall of the groove by the interaction of the ring members.

`My invention has to do with packing of this character, and its object is to provide an improved construction of rings as hereinafter more fully set forth.

lin the accompanying drawings forming a l part of this specification:

Fig. 1 is a perspective view of the rings which embody one form of my invention.

lFig. 2 is a sectional view showing a'portion of a piston and cylinder with the rings 1n assembled position.

lF ig. 3 is an enlarged detail view, and l Fig. a, is a section showing the main packing rlng.

ln the drawings, l is a resilient packing ring, split at 8, as is customary, and of approximately triangular or possibly trapezoidal cross-section. The exterior of this ring conforms to the interior of the cylinderV 2, the one side is adapted to fit one side of the groove 3 in piston 4, and the'other side whose surface is at an oblique angle to the* axis of tlieringis provided with a plurality of ribs 5. A 4spring ring 6, shown in Fig. 2 as of generally triangular section with rounded edges, is adapted to lie in the portion of the piston groove not occupied by ring l. The spring ring 6 is provided at its ends with bent portions 7, adapted to be positioned between any two of the ribs 5 and thereby prevent relative rotative movement of the rings. The ring 6 when in assembled relationship with ring l, will rest against the ribs 5, whereby several points ofengagement may be obtained upon the inner side of the ring in order to exert any even pressure upon the cylinder wall.

llt will be seen that, owing to the angles of the engagingn surfaces, as shown in Fig. 2,

the ringo will tend to force ring 1 into en- 4 gagement both with thecylinder wall and with one wall of the piston groove, thereby completely packing the joint, and thatY any wear will be taken up by a readjustmentof the relative positions of the two rings owing to their lresilience.

l/Vhile l have described in detail one embodiment of my invention, it will be under- 4stood that modifications may be made within the scope of the invention and ll do not y desire to be limited to the exact construction' shown.

li claim: l. In a piston packing, the combination with a resilient split ring having a surface on its inner side oblique to the axis of the ring, said surface provided with raised bear# ing portions arranged at intervals around the ring, of a resilient split expanding ring adapted to be placed with said first mentioned ring in a piston groove and to seat on said bearing portions, the relation ot the engaging surfaces being such that tle expanding ring will operate to Jforce the first mentioned ring Voutwardly and axially when said rings are seated in a piston groove.

2. In a piston packing, the combination of -a resilient split piston ring provided with a surface oblique to its axis and with ribs projecting from said surface, and a spring ring adapted to engage said ribs and provided with deliected end portions adapted tol lie between certain ofsaidrilosg; 3. lin a piston packing-the combinationwith a cylinder and piston, tlie piston loaving a groove, of a ,split packing ring seated in said groove with its exterior surface adapted to engage said cylinder and one side adapted to engage a Wall of said groove, said ring having a third surface oblique .to the first two, said oblique surface provided With ribs, and a resilient ringseated on said ribs and operative to force the split packing ring into engagement With the cylinder and the Wall of the groove.

d. ln a piston packing, theoornliination with a cylinder and a piston having a groove of a resilient split ring in said groove adapted to engage the Wall oi the cylinder and one Wall oi said groove, said ring provided with a surface oblique to its axis and having ribs formed thereon, and a split spring ring with deeoted ends, said last-mentioned ring inraoee adapted to lie upon said ribs with its deflected ends positioned between the ribs, and to torce said first-mentioned ring into engagement With the cylinder and tlie Wall of the groove.l

l5., ln a piston packing,z f-a', oylinder and piston, the latter having a cirenrnferential groove, a single resilient splitpaeking ring seated in said groove andfsjengaging the cylinder Wall andoneWalljoffgtliegroove, a split spring expanding ring-'fof approximately triangular section seated in said groove and engaging said split ring and the opposite Wall of said groove, bearing surfaces loeing provided at intervals upon said lirst mentioned ring upon which said ex= panding ring is seated.

Jln testimony WliereoifI ll aiiixmy signature.,

CHARLES lit. SHGRT, 

